A system for communicating information between circuits is described. A transmit circuit provides pulse-amplitude-modulation (PAM) signals via a communication channel to a receiver. A circuit in the receiver determines digital values from the received signals using a time-varying threshold voltage, which varies during the bit-time. This approach may compensate for inter-symbol interference (ISI) to increase the voltage and timing margins of the system.

Embodiments may provide a way of communicating via an electromagnetic radiator, or light source, that can be amplitude modulated such as light emitting diode (LED) lighting and receivers or detectors that can determine data from light received from the amplitude modulated electromagnetic radiator. Some embodiments may provide a method of transmitting/encoding data via modulated LED lighting and other embodiments may provide receiving/decoding data from the modulated LED lighting by means of a device with a low sampling frequency such as a relatively inexpensive camera (as might be found in a smart phone). Some embodiments are intended for indoor navigation via photogrammetry (i.e., image processing) using self-identifying LED light anchors. In many embodiments, the data signal may be communicated via the light source at amplitude modulating frequencies such that the resulting flicker is not perceivable to the human eye.

Systems an methods are provided that disclose providing a positioning service for devices based on light received from one or more light sources. This light based positioning service uses light information transmitted by each light source to determine the position of the device. The positioning information can include three dimension position information in a building that can then be used to deliver services and information to a mobile device. The content delivered to a mobile device can include multimedia, text, audio, and/or pictorial information. The positioning information along with other location or positioning information can be used in providing augmented reality or location aware services. The light sources can be independent beacons that broadcast information in visible light at a rate that is undetectable by the human eye. Content can be retrieved from a server over a communications connection.

A method of communicating information from a sensor concerning a received signal, comprising: responsive to receiving by at least one detecting sensor, during a defined time interval, data indicative of an entire data of a frequency band received by it during the defined time interval, comprising at least one signal emitted at least one emitter, and to detecting of the emitted signal by the at least one detecting sensor, sending from the sensor assistance information corresponding to the detected emitted signal during the defined time interval, to at least one non-detecting sensor. This information can be utilized by the non-detecting sensor to perform an action with respect to data indicative of an entire data of the frequency band received by the non-detecting sensor during a corresponding defined time interval, the action corresponding to at least one emitted signal received by the non-detecting sensor during the corresponding defined time interval.

A method of tuning a notch filter in a data storage device (DSD) including the notch filter and a shock detection system includes: adjusting pulse width modulator (PWM) frequency settings of a spindle drive signal; detecting a maximum noise level of an output signal of the shock detection system while adjusting the PWM frequency settings; and selecting a notch filter frequency corresponding to a PWM frequency setting at which the maximum noise level of the output signal of the shock detection system is detected.

An apparatus comprising an encoder is configured to: detect a first edge in the input signal and, in response, provide a pulse generation sequence comprising the encoder being configured to: generate, in the output signal, a first pulse, wherein the first pulse is provided over first and second minimum time periods irrespective of an edge subsequent the first edge being present in the input signal; and obtain a first sample of the input signal; and obtain a second sample at an end of the first pulse; and if the first sample and the second sample are indicative of different voltage levels, generate a second pulse; or if the first and second sample and the same maintain the voltage level in the output signal.

Ultra-Wideband (UWB) technology exploits modulated coded impulses over a wide frequency spectrum with very low power over a short distance for digital data transmission. Today's leading edge modulated sinusoidal wave wireless communication standards and systems achieve power efficiencies of 50 nJ/bit employing narrowband signaling schemes and traditional RF transceiver architectures. However, such designs severely limit the achievable energy efficiency, especially at lower data rates such as below 1 Mbps. Further, it is important that peak power consumption is supportable by common battery or energy harvesting technologies and long term power consumption neither leads to limited battery lifetimes or an inability for alternate energy sources to sustain them. Accordingly, it would be beneficial for next generation applications to exploit inventive transceiver structures and communication schemes in order to achieve the sub nJ per bit energy efficiencies required by next generation applications.

When the ultra-low power mm-scale sensor node does not have a crystal oscillator and phase-lock loop, it inevitably exhibits significant carrier frequency offset (CFO) and sampling frequency offset (SFO) with respect to the reference frequencies in the gateway. This disclosure enables efficient real-time calculation of accurate SFO and CFO at the gateway, thus the ultra-low power mm-scale sensor node can be realized without a costly and bulky clock reference crystal and also power-hungry phase lock loop. In the proposed system, the crystal-less sensor starts transmission with repetitive RF pulses with a constant interval, followed by the data payload using pulse-position modulation (PPM). A proposed algorithm uses a two-dimensional (2D) fast Fourier transform (FFT) based process that identifies the SFO and CFO at the same time to establish successful wireless communication between the gateway and crystal-less sensor nodes.

Full-duplex communications over a single-wire bus is described in the present disclosure. In embodiments disclosed herein, a master circuit and a slave circuit(s) are able to communicate forward (master to slave) bus telegrams and reverse (slave to master) bus telegrams concurrently over a single-wire bus consisting of one wire. Specifically, the master circuit is configured to modulate the forward bus telegrams based on voltage pulse-width modulation (PWM), while the slave circuit(s) is configured to modulate the reverse bus telegrams based on current variations. In addition, the slave circuit(s) is further configured to harvest power from the master circuit concurrent to receiving the forward bus telegrams and sending the reverse bus telegrams. By supporting full-duplex communications over the single-wire bus, it is possible to improve efficiency, cost, and power consumption in an electronic device wherein the single-wire bus is deployed.

The present technology relates to a transmission apparatus, a transmission method, and a filter circuit that make it possible to transmit a signal with high quality, the signal including a plurality of signals having different speeds. The transmission apparatus includes a detection unit that detects each of a plurality of signals having different speeds from an input signal. Further, the transmission apparatus includes an output control unit that controls output of an output signal including the plurality of signals, on the basis of detection results of the plurality of signals by the detection unit. The present technology can be applied to, for example, a transmission apparatus that transmits a serial signal conforming to the USB 3.0 standards or a transmission apparatus that converts the serial signal described above into a millimeter-wave signal or an optical signal and sends and receives the signal.